We have substantially improved on the continuous flow blood separator previously developed in this laboratory. Improvements include a redesigned separation chamber which is a narrow spiral, and is tilted away from the axis of rotation. The total volume of the system including the separation chamber and all blood lines, is about 80 ml. One, two or more separation chambers can be built into the rotor, allowing for successive stages of blood separation, such as concentration of platelets, or white blood cells. The rotor now has a self balancing system attached for dynamic balancing. We have also improved on the centrifuge by reducing wear points along the blood tubing. At present, the centrifuge operates well at rotor speeds to 2500 RPM, generating a force of over 400 G. Under these conditions, over 100 ml/min of whole blood can be separated into blood and plasma fractions. Other cell fractions can be harvested in turn from additional stages built into the rotor.